Photonics is the field of technology relating to the generation, transmission, reception and manipulation of light. Photonic devices include for example waveguides, splitters, combiners, wavelength-division multiplexing (WDM) structures, mirrors, gratings, lasers, photodetectors, optical amplifiers, optical modulators, optical filters, optical resonators etc. Silicon photonics (SiP) relates to photonic devices which are based on silicon and has the potential to provide high quality, low cost photonic devices built using silicon chip technologies.